1. Field of the Invention
This invention relates to the field of surgical screws, and in particular screws for use in orthopedic surgical procedures.
2. Description of the Related Art
The related art of the field teaches a number of different types of surgical screws that may be used in a human body for insertion into a substrate, such that said screws are inserted into bones, and whereby tissue or muscle may then cover the head of the screw. Certain inventions disclose surgical screws, and which screws may employ standard driver insertions points that may consist of cruciform recesses, slot recesses, or polygonal recesses. However, a shortcoming of these devices is that they may not lock, or mechanically retain, themselves to a driver head, and thus may have a tendency to fall off the driver head. This shortcoming may result in increased difficulty in their application and further may increase the amount of time required to fasten these screws to a substrate. Another shortcoming of these devices is that they may be designed and manufactured such that the head portion of these screws may have a rough or angular outer surfaces, and which angularity may cause increased irritation of tissue and muscles covering the head of the screw after their application.
Furthermore, there are other teachings that may demonstrate a self-retaining screw to a driver head, however, these devices may also be designed and manufactured such that the screw head may have an outer surface that may be angular or irregularly shaped. Such self-retaining screws may consist of a tapered recess, wings, or twisted hexagonal recesses. A shortcoming of these devices may be that they are weak in structure and may also have a tendency not to tightly secure a driver head, whereby these screws may have a tendency to disengage themselves from the driver head. Furthermore, these devices may be subject to yet another shortcoming that upon insertion to a substrate, the head of these screws may be covered with tissue and/or muscle such that the angular or irregularity may cause increased discomfort and added irritation to the tissue and/or muscle at the insertion site. Additionally, these devices may have a retaining fixture that may not provide strength for a load such that the retaining fixture may be caused to break from the load force required for its insertion into a substrate.
Therefore a need has arisen for an orthopedic screw that overcomes these and other shortcomings of the related art. A technical advantage of the present invention is to provide an orthopedic screw wherein tissue irritation may be substantially reduced and minimized. Another technical advantage of the present invention is to provide an orthopedic screw that may be mechanically retained to a driver head. Still yet another technical advantage of the present invention is to provide an orthopedic screw that may provide for a load-bearing surface having a retaining mechanism located on the same plain, and such that the retaining mechanism will not fail under the necessary load force for insertion into a substrate.
According to an exemplary embodiment of the present invention a self-retaining orthopedic screw is described. The present invention may have a first portion and a second portion, wherein said first portion may comprise a head portion having substantially smooth outer surface and may further comprising a recessed portion on a top surface of said head portion, wherein said recessed portion may comprise a deflection beam having at least one protrusion extending into said recessed portion, wherein said deflection beam may be substantially enclosed within said recessed portion, and wherein said second portion may comprise an elongated portion having a threading such insertion into a substrate is facilitated.
Other objects, features, and advantages will be apparent to persons of ordinary skill in the art in view of the following detailed description of the invention and the accompanying drawings.